Motor-controlling mechanism.



.11 875,982., PATENTED JAN. 7, 1963.

, U H.;W.YC'HBNEY.' MOTOR CONTROLLING MECHANISM.

v APPLIdATIOK FILED MAR. 80. 1907 UNITED STATES PATENT OFFICE.

HERBERT W. CHENEY, OF NORWOOD, OHIO, ASSIGNOR TO ALLIS-OHALMERS COMPANY, A CORPORATION OF NEW JERSEY, AND THEBULLOGK ELECTRIC MANUFACTUR NG COM- PANY, A CORPORATION or orno.

MOTOR -CONTR OLLING MECHANISM.

Specification of Letters Patent.

Patented Jan. 7. 1 08.

Application liled March 30,1907. Serial No. 365.450.

To all whom it may concern:

Be it known that I, HERBERT W. CHENEY, citizen of the United States, residing at Norwood, in the county of'Hamilton and State of Ohio, have invented certain new and useful Improvements in Motor-Controlling Mechinism, of which the following is a full, clear, and exact specification.

, My invention relates to starters for elec- 10 trio motors and more particularly to resistance starters for induction motors.

In my co-pending application No. 320,757, filed June 8, 1906, a resistance starter for. an induction motor is shown. My present invention is an improvement on that shown in said prior application.

In addition to the objects set forth in said prior application my present invention has the further objects of reducing arcing at the controller contacts, of obtaining a quicker action of the short circuiting device, of providing means whereby the operating current for the short circuiting device may flow until its work is done howsoever ra idly the op erator moves the controller, w ilesaid current is stopped as soon as its work is done, of making it impossible to move the short circuiting device by hand into an improper po- 1 sition and leaving it there, and of providing means whereby the position of the short circuiting device may be indicated to a distant operator. I

The novel features of my invention will ap ear from the description and drawing and will be particularly pointed out in the claims. The single figure of the drawing shows diagrammatically one embodiment of my invennion.

An alternating current motor A, here shown as a rotor wound induction motor, is supplied with current by the mains 11, 12 and 13 throu h a switch 14. This switch is biased towar off position by a spring 15, but may be moved into on position by a 46 solenoid 16, in which latter position it is held by a latch 17 until such time as the latch is released'by the energization of a solenoid 18. Thc'circuit of this solenoid 18 may be closed either by a push button 19, or by an overload b0 magnet'20 which is connected to the secondaryof a series transformer 21, the primary of which is the main 13.

The secondary or rotor circuit of the motor A is connected through slip rings 22 to the rotor is broken.

a stationary starting rheostat or variable resistance 23. This resistance is composed of three parts, here shown as star connected to correspond with the connections of the rotor windings. This resistance may be delta connectcd if the rotor windings are so connected, the two generally corresponding. The resistance 23 can be varied by means of a sliding bar 24, movable by a handle 24 over the contacts of the resistance 23.

Within the slip rings 22 is a poWer-operated device 25 for internally short circuiting the rotor windings. This device may be of any desired construction, but, as shown, should be'so arranged that it can rotate with the slip rings. This device is movable along the shaft of the motor A, and in its inner or operative position connects or bridges the slip rings 22 to internally short circuit the-rotor windings by engaging the inward projections 26' from said rings. In its outer position the device 25 is out of engagement with the projections 16 and the internal short circuit of This short circuiting device is movable into and out of short circuiting position bymagnets or solenoids 27 and 28 respectively. It may also be moved" by the handle 45. Resistances 29 and 30 are connected across the windings of the magnets 27 and 28 respectively. The circuits of magnets 27 and 28 are controlled by solenoidoperated switches 31 and 32, the solenoids 33 and 34 of which are controlled by an extension 35 from the bar 24. Switches 37 and 38 are also in circuit with the solenoids 33 and '34 res ectively, these switches being raised from t eir lower positions by the final movements resulting upon energization of the solenoids 27 and 28 respectively. The switch 38 when in its upper osition, completes the circuit of a lamp 36 w ich when lighted indicates that the short circuiting device is in its outer position. The circuit of the solenoid 33 is I completed when the switch 37 is down and.

the bar 24 and its extension 35 are in position 8, and is broken by either the raising of the switch 37 or the movement of the arm 24 out of position 8. The circuit of solenoid 34 is completed when the switch 38 is down and the arm 24 is in any position except position 8, and is broken either by the raising of the switch 38 or by the movement of the arm 24 to osition 8. 1

he solenoids 27 and 28 are supplied with .3 closed by the latch 17.

. the voltage between the outside mains of the three wire system 41, 42 and 43, while the solenoids 16, 18, 33 and 34 and the lamp 36 are supplied with the voltage between the 5 neutral wire 42 and one of the outside mains.

This arrangement is shown merely as a convenient one, as in practice any other source or sources of current supply may be used if desired. When the arm 24 and its extension 35 are in position 0, the circuit of solenoid 16 may be completed by depressing push-button 40.

The operation of the system is as follows: With the parts in the positions shown the supply circuit of motor A is open, the resistance 23 is in the rotor circuit of the motor, and the short circuiting device 25 is in its outer position. Should the short circuiting device be moved in, intentionally or acciden- 20 tally, the switch 38 is momentarily closed in its lower position, vand the circuit of the solenoid 34 being thus completed, the switch 32 is also closed to ener ize the magnet 28 to niove the short circuiting device out again immediately. The lamp 36 indicates to the operator when the short circuiting device is in its outer position. By depressing the push-button 40 the current-admitting switch 14 isclosed by the solenoid 16 and is held As the motor A starts and begins to increase in speed the bar 24 or master controller is moved slowly toward the right, thereb gradually cutting the resistance 23 out o the rotor circuit of the 111.. ;or,' to cause further increase in the motor speed. When the bar 24 reaches posi tion 8, its positionof lowest resistance, the tension com letes the circuit of the solenoid 33 and said so enoid closes the switch 31 to 40 energize the magnet 27 to move the short circuiting device 25 into engagement with the projections 26, thereby internally short circuitingtherotorwinding. This is the normal running position of the parts. As the device 25 rotateswith the slip rings there are no disadvantages arising from the sliding contacts between slip rings 22 and the brushes which bear thereon. By this movement of the short circuiting device the switch 37 is raised to deenergize the solenoid 33 and the magnet 27.

Thus the current in these windings flows as long as it has work to do and no longer. The

movement due to the magnet 27 also allows the switch 38 to drop to extinguish the light 36 and make it possible for the circuit of solenoid 34 to be completed by the bar Should an overload occur the solenoid 20 is energized sufficiently strongly to raise its switch, thus closing the circuit of solenoid 18'to trip the switch 14 and cause the motor to stop. The motor may also be stopped when desired by depressing push-button 19 to cause a similar tripping of the switch 14.

Once the switch 14 is opened, the motor can not. be started again until the bar 24 has Ydevice; ;25 out of bridging position.

at the switches 37 and 38 respectively.

been moved into position 0. As the arm 24 leaves position 8, whether for the purpose-of preparing to start the motor again or of allowing the motor to slow down, it'at once by its extension 35 closes the circuit of solenoid 34, and the latter closes switch 32 to energize the magnet '28 to move the short circuiting This movement of the short circuiting device raises the switch 38 and allows the switch 37 to drop, so that the solenoids 28 and 34 are deenergized as soon as their work is done, while they remain energized until then vhow-v soever rapidly the arm 24 is moved back ward. i

Should the short circuiting device 35 beintentionally or accidentally moved out of its bridging or operative position to close the switch 37 when the bar. 24 is in position 8, the magnet 27 is momentarily energized to '5 move said short circuiting device immediately back to its bridging position. ,Thus the short circuiting device is maintained in its inner position when the arm 24 is in position 8 and in its outer position when said arm is in any other position.

None of the sparking which occurswhen the various circuits which contain solenoids are interrupted takes place at the. contacts cooperating with the extension 35. The circuits of the solenoids 33 and 34 are broken The circuits of the magnets 27 and 28 are broken at the switches 31 and 32 respectively and the sparking at these switches is reduced by having resistances 29 and 30 connected around magnets 27 and 28 respectively.

Many modifications of the precise arrange ments here shown and described may be made without departing from the spirit and scope of my invention, and all such modifications I aim to cover in the. following claims.

What i claim as new is 1. In combination, a device for internally bridging the slip rings of a rotor wound induction motor, two magnets torrespectively moving said device into and out of bridging position, and two switches respectively con trolling said magnets and arranged to be automatically opened upon the movements caused by their respective associated magnets. Y

2. In combination, a device for internally bridging the slip rings of a rotor wound induction motor, a plurality of magnets for operating saiddevice, 'and a switch controlling each of said magnets which is automatically opened upon the movement caused by its associated magnet.

3. In combination, a device for internally bridging the slip rings of a rotor wound induction motor, a magnet for operating said device, a resistance connected across said magnet, and a switch in the circuit of said each magnet, and a magnet which is automatically opened upon v the operation of the bridging device.

4. In combination, a device for internally bridging the slip rings of a rotor wound induction motor, two magnets for moving said device into and out of bridging position respeotively, a resistance connected across each magnet which is opened upon the movement caused by its associated magnet.

5. In combination, an induction motor, an external resistance in the secondary circuit thereof, magnetically operated means in the motor for short circuiting said resistance and i a resistance in shunt to the energlzmg wmd ing of said means.

6. In combination, an induction motor,

an external resistance in the rotor circuit means for indicating the position of'. said circuiting means when device.

8. In combination, an induction motor, a resistance in the secondary circuit thereof, power-operated means for short-circuiting said resistance within the motor, and a device for indicating the position of said means.

9. In a starter for an induction motor, the combination with said motor, of a resistance in the rotor circuit thereof, means for gradually' cutting out said resistance, automatic means for internally short circuiting the rotor windings when said resistance has been fully I cut out, and a device for indicating at a distance the position of said short circuiting means. i 1

10. In combination, a device'jfor internally bridging the slip irings of a rotor wound induction motor, a pl rali'ty of magnets for operating said device,l (1 means for automatically opening the magnetsas soon as that magnet'has accomplished its work. 5 a

, 11. In combination, device for internally bridging the slip gs of a rotor wound induction motor, twollmagnets for moving said device into and\ oiit lof bridging position respectively, and meahs I or openingthe circuit of either magnet as oon as that agnet has accomplished its .work, 3

12. In a starter fora induction motor, the combinationwith sa d motor, of a rheostat in the rotor circuit there'of, means for short circuiting the rotor'windings internally, means for automatically operating said short the rheostat is moved into its position of lowest resistance, for

switch in the circuit of .and means for v I .magnetic means as soon as it'has completed its work.

ci cuit of each of said opening the short circuit when the .rheostat is moved out of said position, and means for deenergizing said operating means ,as'soon as its work is done. v

13. In a starter for an induction motor, the combination'with said motor, of a rheostat in the rotor circuit thereof,means which in one position shortcircuits the rotor winds ings internally, electromagnetic means for moving said short circniting means into. operative 'pbsition when the rheostat-is moved into its position of lowest resistance,

' and for automatically opening said short cir cuit when it is movedout of said position,

deenergiz ng said electro- 14'. In combination,- an induction motor, a rheostat in the rotor circuit thereor, means for'internally short circuiting the rotor windings, two magnets for respectively moving said means into and out'of operative .position, and connections whereby the first magnet is energized whenever the rheostat is in its position of lowest resistance and said means is not in operative position, and

the second magnet Whenever the rfheos'tat is in other than its position of lowest resistance and said means 18111 operative position.

15. In combinatioman induction motor having a wound secondary member, meansl for short circuiting'said secondary member, a magnet for operating said short circuiting means, and a magnetically operated switch for controlling the circuit of said operating means:

16. In combination, an induction motor having a ound secondary member, meansfor short circuiting said secondary member, two magnets for respectively moving said short circuiting device into and out of short circuiting position, and'two electromagnetically operated switches for controlling the circuits of said respective magnets.

17. In combination, .an induction motor. having a wound secondary member,-means for short circuitingsaid secondary member, a magnet for o erating said shortfcircuiting means, an e ectromagnetically operated switch for controlling the circuit of said .magnet, and means for deenergiz-ing the magnet of said switch when said first mentioned magnet has completed its work.

18. In combination, aninduction motor having a wound secondary member, means for short circuiting saidsecondary member,

two magnets for respectively moving said short circuiting device into and out of short circuiting position, two magnetically operf ated switches for controlling the circuits 0 said respective magnets, and means for deenergizing the magnets of said switches when said short circuiting device is moved into and out of short ciroulting position-respectigely. 19. Infcombination, an induction motor having a wound secondary member, a resistance 1n circuit with said secondarymember,

means for varying said resistance, means for short circuiting said secondary-member, a

"magnetfor operating said short circuiting means, and an electromagnetically operated switch for controlling the circuit of sand magnet, the circuit of the crating magnet of said switch being contro led by the position of said resistance-varying means.

20. In combination, an induction motor having a wound secondary member, a resist ance in the circuit of said secondary member,

means for varying said resistance, means for short circuiting the winding of said secondary member, magnets for respectively moving said short circuiting means into and out of short circuiting position, magnetically operated switches for controlling the circuits of said respective magnets, and means forcontrolling, the circuits of. the operating magnets of said switches by the position of said resistance-varying means. I

21. In combinatiom'an induction motor ;having a would secondary member, a resist-- 'ance in circt'it with said secondary member, means for varying said resistance, means for short circuiting said secondary member a magnet. for operating said short circuiting means, a magnetically operated switch for controlling the circuit of said magnet, and meanslfor controlling the circuit of the operating magnet of said switch by the osition of said resistance-varying means and of said short circuiting means. Y I

22. In, combination, an induction motor having a wound secondary member, a resistance in the circuit of said secondary member, means for varying said resistance, means for short circuiting the winding of said secondary member, magnets for respectively moving said short circuiting means into and out of short circuiting position, and electromagnetically operated switches for controlling the-circults of said respective magnets, the circuits of the operating magnets of said switches being controlled by the position of said resistance-varying means and of said short circuiting means.

23. In combination, an induction motor having a wound secondary member, a resistance in the circuit of said secondary member, means for varying said resistance, means for short circuiting the winding of said secondary membernnagnets for respectivelvmoving said short circuiting means into and out of short circuiting' position, and 'electromagnetically o erated switches for controlling the circuits .0 said respective'magnets, the operating circircuits of said respective magnets, the oper-..

ating circuits of said switches being completed by the movement of said resistancevarying means into and out of its osition of lowest resistance respectively, and roken by the movement of said short circuiting means .into and out of short circuiting position respectlvelv.

25. In a starter for an induction motor, thecombination with said motor, of a rheostat, in therotor circuit thereof, means which in one position short circuits the rotor windings internally, and electromagnetic means for automatically moving and maintaining said short circuiting means in operative position when the rheostat is in its position of lowest resistance and for automatically opening and maintaining open said short circuit whenthe rheostat is in any other position.

In testimony whereof I aflix my signature, in the presence of two witnesses.

HERBERT W. CHENEY.

\Vitnesses GEO. B. SCHLEY, FREn- J. KINSEY. 

